Tested at 20km/h; IIRC that's how normal bike helmets are tested too.
My problem is, I'd bet that crashes causing serious harm happen way faster than that: 20km/h is the average speed of a champion marathon runner, and no one runs with an helmet. My 2nd guess as to why is that if helmets were effective when it matters, at higher speeds, they would look very similar to a motorcycle helmet, and be impractical.
So, facing the choice between something that does its job, and something ineffective but slightly less impractical, lawmakers try to make the latter mandatory. It reminds me of the TSA "security" policies...
My problem is, I'd bet that crashes causing serious harm happen way faster than that: 20km/h is the average speed of a champion marathon runner, and no one runs with an helmet. My 2nd guess as to why is that if helmets were effective when it matters, at higher speeds, they would look very similar to a motorcycle helmet, and be impractical.
So, facing the choice between something that does its job, and something ineffective but slightly less impractical, lawmakers try to make the latter mandatory. It reminds me of the TSA "security" policies...